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摘要: 采用原位红外光谱、拉曼光谱、紫外光谱和H2-TPR表征技术对CoMo/Al2O3-SiO2催化剂进行了表征。结果表明,增加CoMo/Al2O3-SiO2催化剂中的SiO2含量会促进八面体配位钼物种向四面体配位钼物种转变,SiO2含量越高这种结构转变趋势越显著。在CoMo/Al2O3催化剂载体中加入适量的SiO2能够改变载体与活性金属的相互作用,提高了催化剂加氢脱硫活性。
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关键词:
- CoMo/Al2O3-SiO2 /
- 原位红外光谱 /
- CO吸附 /
- 硫化
Abstract: The characterization of a series of CoMo/Al2O3-SiO2 catalysts with different SiO2 contents were studied using in-situ FT-IR, Raman, UV-Vis and H2-TPR techniques. The results show that the increase of the silica component in CoMo/Al2O3-SiO2 catalysts can promote the transformation of octahedral molybdenum species into tetrahedral molybdenum species, and the higher SiO2 content can contribute to the transformation. Proper amount of silica component in the mixed supports can alter the interaction between the support and the active metals, resulting in higher hydrodesulfurization(HDS) activity of CoMo/Al2O3-SiO2 catalysts.-
Key words:
- CoMo/Al2O3-SiO2 /
- in-situ FT-IR spectroscopy /
- CO adsorption /
- sulfidation
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表 1 SiO2含量对硫化态CoMo/Al2O3-SiO2催化剂MoS2和CoMoS峰面积的影响
Table 1 Effect of SiO2 on MoS2 and CoMoS sites of sulfide CoMo/Al2O3-SiO2
Catalyst Peak area of 2110 /cm-1 Peak area of 2070 /cm-1 Peak area of 2025 /cm-1 0Si 0.008 0.018 0.004 2Si 0.058 0.114 0.036 10Si 0.029 0.063 0.014 15Si 0.018 0.046 0.013 20Si 0.011 0.028 0.006 -
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